Biochemical and immunohistochemistry of sublethal effects thiamethoxam on the Apis mellifera Hymenoptera, apidae) africanized

Abstract

Honeybees Apis mellifera Africanized species have great economic and ecological importance, because they are pollinators of agricultural crops and natural areas, and produce honey, beeswax, propolis and royal jelly. In recent decades there has been an increase in global agricultural production and consequently the use of insecticides in crop fields was higher, affecting non-target insects such as bees. The thiamethoxam is a neonicotinoid insecticide used to combat insect pests in various crops such as citrus, coffee, and sugar cane. This insecticide acts on the central nervous system of insects, including both adult bees, the larvae through contaminated pollen and nectar. Considering the effects that can be caused by thiamethoxam, this study aims to assess the possible toxic effects of sublethal doses applied in larvae of A. mellifera during all stages of development. After establishing the lethal dose (LD50) of thiamethoxam for larvae, will be adopted DL50/10 sublethal dosages; DL50/20 DL50/50 and that will be used in the experiments of acute intoxication by contact. Will be observed any abnormalities in the developmental stages of larvae and mortalities recorded. After sublethal toxicity bioassay will also be analyzed, survival and longevity. The brain of larvae, pupae and newly emerged workers will be dissected and subjected to confocal microscopic analysis, and enzymatic analysis.